Automatic spark-retarder



F, H. SMITH.

AUTOMATIC SPARK RETARDER.

APPLICATION r1150 0CT.9,1919.

1,368,581, Patented Feb. 15,1921.

IIIIIIIIII/ UNITED STATES PATENT OFFICE.

FRANK H. SMITH, OF DETROIT, IrIICHIGAN.

AUTOMATIC SPAEK-BETABDER.

Application filed October 9, 1919.

T 0 all whom it may concern.

Be it known that I, FRANK H. SMITH, a citizen of the United States, residing at Detroit, county of IVayne, State of Michigan have invented a certain new and useful Improvement in i-rutomatic Spark-Retarders, and declare the following to be a full, clear, and exact description of the same, such as will enable others skilled in the art to which it pertains to make and use the same,

reference being had to the accompanying.

drawings which form a part of this specification.

This invention relates to mechanism de signed to automatically retard the spark and prevent a premature explosion during the cranking of an internal combustion engine, and is here shown as being attached to the engine of a Ford car in connection with which it is particularly adapted to be used.

In the drawings,

Figure 1 is a front elevat1on of a Ford motor taken on the line I--I of Flg. 2.

Fig. 2 is a fragmentary crosssectional view.

Fig. 3 is an illustration of the band identified by the letter i.

Fig. I shows a modified form of the ratchet carried by the starting crank.

In the drawings, 64 represents the conventional motor assembly, I) the commutator, c the rod which constitutes the connection means between the spark-control lever on the steering wheel and the commutator. d is the starting crank mounted in bearings c and provided at its inner extremity with a starting ratchet 7 which is adapted to en-' gage a pin 9 carried by the crank shaft h.

A band 11 is provided which encircles the starting crank and in use on a Ford car would be of the form here shown adapted to encircle the starting ratchet f and to be firmly held in place thereto. This band is provided with lugs j in such number as may be described, four being here shown. The band here illustrated is made in halves adapted to be secured together by means of bolts 76. A preferred form might be to provide a special design of starting ratchet as shown in Fig. 4, in which the ordinary form of ratchet adapted to be secured to the starting crank would be provided with integral radial lugs Z. This provision of radial lugs on the starting ratchet wouldprevent any trouble which might arise due to the loosening of the clamp band i as the starting Specification of Letters Patent.

Patented Feb. 15, 1921.

Serial No. 329,577.

ratchet would be held in place in the usual manner now provided.

There is likewise provided a system of linkage attached to the front of the motor connected at one end with the rod 0 and adapted to intercept and be set in motion by lugs 7' or Z carried by the band 2' or the starting ratchet f.

Comprising this linkage is a lever m pivoted to a bolt'or stud a. This lever m is provided at its lower extremity with a friction roller m The bolt n is one now used in Ford construction and is merely extended to provide pivoting means for such lever on. A transverse lever 0 is pivotally connected with lever m at one end, the other end being formed to receive the rod 0, as shown. The

spark retardation.

The commutator here shown is adapted to be moved by the rod 0 in the direction of retardation of the spark.

Itis thought that the operation of the device is apparent from the above description.

In the cranking of the motor it is desirable that combustion in the cylinders be delayed so as to prevent the occurrence of a premature explosion which might result in a back kick with consequent injury to the one starting the motor.

This has proved to be a frequent occurrence in the hand cranking of internal combustion engines and the sprained and broken wrists and arms resulting therefrom are without number. The spark is advanced too far, either through oversight, ignorance or faulty connecting means, and the explosion occurs before the piston has arrived at the top-most point of the compression stroke.

When it is desired to start the motor, starting crank (Z is pushed inward until the ratchet f engages the pin 9 of the crank shaft. This brings the lugs carried by the band 2 in position to be intercepted upon rotation of the starting crank by the friction ated to retard the production of the spark and during the time the linkage remains in this position the explosion in the combus tion chambers will be delayed until the piston has reached its maximum compression stroke. Should there he an advance of the spark due to any cause, with consequent actuation of the linkage further rotation of the starting crank would bring the lugs into engagement with the friction roller m again moving the commutator so as to retard the spark. 7

Claims:

'1. In a spark-retarding attachment for Ford engines, a hand crank, a clamping ring provided With radially-projecting lugs, such ring adapted to be removably secured to the hand-crank atthe ratchet end thereof, a system of linkage adapted to hepivoted to the engine, one end of such linkage adapted to be pivoted to the commutator the other end of said linkage adapted to be positioned in the path of revolution of the radially-projecting lugs on the clamping ring so as to intercept the same and he moved aside thereby When the hand-crank is rotated in the cranking of. the engine, in such a manner as to actuate such linkage to move such commutator so as to retard the production of a circuit therethrough.

2. In a spark-retarding attachment for Ford engines, a hand-crank, a clamping ring provided With radially-projecting lugs, such ring adapted to be removably secured to such hand-crank at the ratchet end thereof, a commutaton means for actuating such commutator so as to retard or advance the formation of a spark therethrough, such means adapted to be actuated so as to move said commutator to the retard position by intercepting the revolution of the lugs on the hand-crank during the rotation of the crank in the cranking of the engine.

" in testimony whereof I sign this specifiation.

Y FRANK H SMITH. 

